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MG Midget and Sprite Technical - Alternator mount on water pump

I'm in the process of converting my 68 1275 from dynamo to alternator. I've removed the dynamo, and have offered up the alternator and the replacement bracket that fits on the side of the block. (12G1053)
The brackets don't line up, so I'm now wondering if there's more than one alternator rear mount bracket, or if the cast iron water pump might be different to the more modern ali bodied ones?
(Or perhaps the bracket I bought is just poorly made...)
The dynamo fitted OK, or at least, it never threw a belt in the five years I've had the car.

If I run a close fitting bar through the pump mount it comes out almost a full hole's worth higher than the actual hole in the bolt on bracket.

Do I just take a file to the two mounting holes on the rear bracket, or am I missing something obvious?

Ta, Mark
M Crossley

It should just align. My aftermarket bracket came with slotted holes where it bolts to the block. Perhaps yours is specially supplied for DIY filing fanatics?
Guy W

agreed, an original bracket has slotted holes for perfect adjustment.
David Smith

The bracket is slotted, but not vertically


Dave O'Neill2

Further to the above, there shouldn't be any difference between the cast iron and ally water pump mounts.

The two water pumps are interchangeable, without the need to change generator brackets.
Dave O'Neill2

also be aware that the spacer tube in the L/H alternator mount is movable to mate up to the bracket once the latter is in the correct position.
David Smith

Mark,
previously I think a chap had problems because he had the front slotted adjuster bar bracket fitted wrong but in your case I wonder if like on one of my alternator changes that you might be missing the metal spacer for the top hole on the alternator to water pump, I just used three washers to get the belt to line up with the pulley (37cm belt as pointed out by David Smith in a previous thread)

ETA: David mention your name and you appear - please note I was typing this as you posted so didn't know you were here or see your post - but this is the second time this week we've agreed ! (mk3 spoke steering wheel)
Nigel Atkins

Thanks for the help and suggestions.
If all the water pumps have the alternator mount in the same position, then I'll modify the rear bracket to suit.
At the moment it looks like I'll have to slot the two holes (as shown in Dave Neill's pic) vertically, to lift the bracket by about 1/4". Then the two alternator pivot bolts will be aligned with the block/head joint and the alt pulley will be in the same plane as the crank and water pump pulleys.

Ta, Mark
M Crossley

My bracket is like the one Dave posted the photo of. The holes are elongated for horizontal adjustment, but this also allows for some pivoting movement which raises or lowers the bolt hole for the alternator. I also use two separate short bolts, not one long one so the alignment is easier. It isn't straining the alternator either - its been on there for about 8 years now with no problems at all.
Guy W

Mark is it that you have an alternator that's not a Lucas 16/17/18
Nigel Atkins

Hi Nigel,

Yes, it is a 16ACR. The alternator itself is fine. In fact I've just done the exact same proceedure on my daughter's Minor. (I like to practice on her car first)
I realise that the two pivot positions take seperate bolts and that I can slide the alt back and forth to align with the plane of the other two pulleys. The problem I have is the rear bracket is too low, so that if I just jammed the bolts in, the alt body would "point upwards" a bit. I think the alternator ears would be stressed once the bolts were tightened as well.
If all the water pumps are the same (i.e. there are none with a lower alt mounting) then I'll slot the rear bracket mount holes to move the bracket upward 3/8" or so.
Once I've got the pivot-y bit sorted, then I'll sort the slotted adjuster-y bits.

Ta Mark
M Crossley

Mark,
I think this is another case of photos might help so if you're able to post any

now it might be possible (hush my mouth) that your bracket has been made wrong so perhaps a drawing with dimensions to compare against with brackets that are already fit well
Nigel Atkins

I know of at least 2 different types of bracket for the rear mount. I think the wrong one is from a transverse engine
Rob Armstrong

AFAIK the transverse engine uses the same bracket, as the mounting holes are in the same place and the water pumps are interchangeable.

In fact, my Sprite had a Mini alternator bracket.

The A+ bracket is different, as the mounting holes were further forward, towards the water pump.
Dave O'Neill2

AFAIK the transverse engine uses the same bracket, as the mounting holes are in the same place and the water pumps are interchangeable.

In fact, my Sprite had a Mini alternator bracket.

The A+ bracket is different, as the mounting holes were further forward, towards the water pump.
Dave O'Neill2

Here's a pic of the bracket. I've used one like this for my daughters Moggie 1098.


M Crossley

And here's the bracket in situ. Note the misalignment of the 8mm bar with the hole in the bracket.
Because I'd used that type of bracket before and because the wate pump looked unusual (Its cast iron without a bypass hose casting) I first suspected that it was the pump that was from another application.
But if all the pumps are functionally the same, then it must be the bracket that's poorly made or the block thats tapped incorrectly. The dynamo fitted ok which rules out the block, so I'll modify the bracket.

Sorry for making a mountain out of a molehill. I just didn't want to modify the bracket and then go through the rigmarole later if the water pump was replaced and didn't line up again!


M Crossley

Mark,
unless it was you that elongated those rear fixing holes on the bracket then your bracket doesn't look as well finished as that black bracket Dave posted

your pump *looks* right in that photo, there was a chap from Aus on here that had a pump that wasn't horizontal so perhaps you could also check for that, look at the pump from the front of the car, does the top of the pump look like it's leaning to one side
Nigel Atkins

Is that an optical illusion, or am I right in thinking that your test rod isn't parallel to the top of the block?

Maybe the hole drilled through the pump isn't at right angles to the face of the casting either? If not, then a few minutes with a rat tailed file might just get it sorted.
Guy W

hmmm where did the pump come from? Cast iron pumps haven't been made since the 70s AFAIK and I've never seen one without a bypass hose. This could well be the clue. Also your bracket looks home modified or is that just an illusion of the pic? My original spares are same as Dave O's pic.


David Smith

woohoo looks like another thorough clean and flush of the cooling system - well might as well if that pump's coming off
Nigel Atkins

Brkt pic shows finish as delivered from MGOC. Holes are slightly elongated horizontally. Marks in plating are from spring washers during trial fit.
Other pic shows bar pointing slightly uphill, to illustrate misalignment. The water pump was on the car when I bought it. I checked with a magnet, it's CI. No bypass. The head matches and there was no 'stat in place. I never thought to check for the last 5 years.
I'm building another motor and 5-speed, but it won't be ready for a while, so I'm"borrowing some of the ancillaries. Perhaps I should have left well alone, but whilst I was fixing a radiator leak I got carried away.

Mark
M Crossley

very odd Mark, certainly didn't leave the factory like that so I wonder who, why, and where did the pump come from.
David Smith

It's possible to install a water pump crooked if the pump is missing its locating dowel(s).
Growler

This thread was discussed between 15/08/2013 and 18/08/2013

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